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TACC and AutoSteer Slamming on the Brakes

I remember reading in the past that people had issues with the car slowing down significantly when there was a car on the shoulder and some even reported the car getting confused with overhead structures and overhead road signs and slowing. A few times today on the way home using TACC and AutoSteer (when traffic was slow enough) my car would hit the brakes when going under road signs. At one point a very scary beeping sound came on and the car braked extremely hard and I had to punch the accelerator so I wouldn't get rear-ended (I was using TACC at this point). I know with AP2 this is all still early and in beta, but is anyone else experiencing this when going under highway road signs?

I remember reading in the past that people had issues with the car slowing down significantly when there was a car on the shoulder and some even reported the car getting confused with overhead structures and overhead road signs and slowing. A few times today on the way home using TACC and AutoSteer (when traffic was slow enough) my car would hit the brakes when going under road signs. At one point a very scary beeping sound came on and the car braked extremely hard and I had to punch the accelerator so I wouldn't get rear-ended (I was using TACC at this point). I know with AP2 this is all still early and in beta, but is anyone else experiencing this when going under highway road signs?

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The car slowing down significantly when a car was on the shoulder was related to a safety feature they added to an update to 8.0 on AP1 cars. That feature was either removed or corrected in the next update or at least that's what Tesla claims. It only impacted while driving with AP (TACC plus lane steering).

On AP2 there have been numerous reports of false braking while under TACC. I'm a little alarmed that they didn't correct that since it was initially reported by the 1000 Californians that got it early.

I get false FCW's occasionally with AP 1.0 since the release of 8.0, but they never slow the car down. They just beep and in the IC it shows the car way ahead. So I just shrug and then make a mental note to report it as I've been annoyingly reporting all false FCW's. I do because I'm concerned that in some future updates the same thing will happen with AEB which would be really bad.

The car slowing down significantly when a car was on the shoulder was related to a safety feature they added to an update to 8.0 on AP1 cars. That feature was either removed or corrected in the next update or at least that's what Tesla claims. It only impacted while driving with AP (TACC plus lane steering).

On AP2 there have been numerous reports of false braking while under TACC. I'm a little alarmed that they didn't correct that since it was initially reported by the 1000 Californians that got it early.

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Okay good to know about the shoulder slowing down issue not being a problem anymore. The pucker factor is high going under these highway signs now. The car seems to react to about 20% of them. Never thought I would be hovering over the accelerator instead of the brake.

Okay good to know about the shoulder slowing down issue not being a problem anymore. The pucker factor is high going under these highway signs now. The car seems to react to about 20% of them. Never thought I would be hovering over the accelerator instead of the brake.

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Have you reported these issues to the email address on the release notes?

Unfortunately you're in the position of being a beta tester of not just something that is slightly beta, but is REALLY beta.

I have AP1 and I have noticed that I get FCWs much more often than I used to. I have it set to medium. I think they have increased the sensitivity and I find it annoying. I have thought about changing my setting to low.

Have you reported these issues to the email address on the release notes

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I am going to record my commute tomorrow. I know there is a way to use the voice control to report bugs to Tesla, but at the time I was worried about causing an accident or looking like an A-hole slamming on my brakes for no reason.

I am going to record my commute tomorrow. I know there is a way to use the voice control to report bugs to Tesla, but at the time I was worried about causing an accident or looking like an A-hole slamming on my brakes for no reason.

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I wouldn't use the voice control because it likely has to go through layers of people at Tesla to reach where it needs to go. Instead I'd use the email address to contact the autopilot people directly.

I have AP1 and I have noticed that I get FCWs much more often than I used to. I have it set to medium. I think they have increased the sensitivity and I find it annoying. I have thought about changing my setting to low.

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In seems to have correlated with the radar change when they changed it to see 2 cars ahead, and where it can sense (but, not react) to stopped cars. Ever since then I've had a handful of them. I don't have a dash cam so I can't go back to see exactly what they may have triggered off of. It never seems to be in a particular spot.

I remember reading in the past that people had issues with the car slowing down significantly when there was a car on the shoulder and some even reported the car getting confused with overhead structures and overhead road signs and slowing. A few times today on the way home using TACC and AutoSteer (when traffic was slow enough) my car would hit the brakes when going under road signs. At one point a very scary beeping sound came on and the car braked extremely hard and I had to punch the accelerator so I wouldn't get rear-ended (I was using TACC at this point). I know with AP2 this is all still early and in beta, but is anyone else experiencing this when going under highway road signs?

Click to expand...

Installed the new update on MS HW2 last night. The morning commute was a combo of TACC and not. At one point with TACC on, it did hit the brakes for a car waiting in the adjacent left turn lane on the highway I was on as I approached it. Took control and hit the accelerator immediately to avoid getting rear-ended, but understand it is day one, and things will improve with time. As the release notes indicate, we need to be vigilant as we are all collective beta testers for the hardware and software. Beyond that incident, TACC seemed to work quite well.

This is where fleet learning comes in handy. Initially, the vehicle fleet will take no action except to note the position of road signs, bridges and other stationary objects, mapping the world according to radar. The car computer will then silently compare when it would have braked to the driver action and upload that to the Tesla database. If several cars drive safely past a given radar object, whether Autopilot is turned on or off, then that object is added to the geocoded whitelist.

When the data shows that false braking events would be rare, the car will begin mild braking using radar, even if the camera doesn't notice the object ahead. As the system confidence level rises, the braking force will gradually increase to full strength when it is approximately 99.99% certain of a collision. This may not always prevent a collision entirely, but the impact speed will be dramatically reduced to the point where there are unlikely to be serious injuries to the vehicle occupants.

For those of you that experienced the issue, how strong is the breaking? Do you have time to react? For example let's say you go 65 m/h on a highway and it happens, if you react as soon as possible, at what speed you take control of the car? 45 m/h? 35 m/h?

great post! btw I verified yesterday that HW2 *does* see one or two cars ahead when TACC is enabled. This is what I believe Tesla refers to in this paper as the hardware able to 'bounce the radar signal under a vehicle in front".

For those of you that experienced the issue, how strong is the breaking? Do you have time to react? For example let's say you go 65 m/h on a highway and it happens, if you react as soon as possible, at what speed you take control of the car? 45 m/h? 35 m/h?

Also, is just pressing the accelerator pedal enough to take control?

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I went from 65 to 45 in what felt like less than a second. Hitting the accelerator gave me back total control of the car.
Coming home today in the same lane at the same speed it didn't happen. Only difference I noticed was it was overcast and there weren't giant contrasting shadows on the ground. Not sure if camera vision overrides radar in the front of the car or not.

For those of you that experienced the issue, how strong is the breaking? Do you have time to react? For example let's say you go 65 m/h on a highway and it happens, if you react as soon as possible, at what speed you take control of the car? 45 m/h? 35 m/h?

Also, is just pressing the accelerator pedal enough to take control?

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HW1 here. 2x today on autopilot radar picked up overhead signs and braked from 65 to 40ish. . Both times no alert from car at all... Both times had to manually accelerate to avoid causing a pileup

Sudden braking and the alarm have happened for me twice since the SW update this week. I was not one of the first 1000. Once was going under an overpass and the other was when going on a bridge. Both TACC only on the freeway. I reported the first one to my service center, who requested an email. I did not report the 2nd.

I trust the SW will learn when drivers don't react to these 'triggers' and will stop doing so as well.

I also had an AP1 car. AP2 is clearly learning.

It is not near as smooth as AP1

Braking is harder

Reaccelerating from a stop is painfully slow. i.e.

There is much more lag time before TACC adjusts to keep up with the car in front after that car speeds up after slowing (freeway speeds)

The lines indicating the edges of the lanes jump around on the screen

The car in front jumps around on the screen and sometimes shows in the wrong lane

But this is to be expected. While a bit of a pain now, it will be well worth the wait. AP1 was really good.

In seems to have correlated with the radar change when they changed it to see 2 cars ahead, and where it can sense (but, not react) to stopped cars. Ever since then I've had a handful of them. I don't have a dash cam so I can't go back to see exactly what they may have triggered off of. It never seems to be in a particular spot.

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I just turned my warning down to "late" to see what the change will be. I have been getting the warnings daily in normal driving. I especially get them in parking garages while winding my up past the parked cars.

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